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991.
Yukun Wang Feng Chen Zhuoxin Liu Zijie Tang Qi Yang Yan Zhao Shanyi Du Qiang Chen Chunyi Zhi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(44):15854-15858
Multiple stretchability has never been demonstrated as supercapacitors because the hydrogel used cannot fully recover after being heavily deformed. Now, a highly reversibly stretchable all‐polymer supercapacitor was fabricated using a developed double network hydrogel (DN hydrogel) as electrolyte and pure polypyrrole (PPy) as electrode. The DN hydrogel provides excellent mechanical properties, which can be stretched up to 500 % many times and then restore almost 100 % of the original length. To fabricate the fully recoverable stretchable supercapacitor, we annealed a free‐standing pure conducting polymer film as electrode so that the electrodes induced retardance is minimized. The as‐fabricated DN hydrogel/pure conducting polymer supercapacitors can be perfectly recovered from 100 % strain with almost no residual deformation left and the electrochemical performance can be maintained even after 1000 stretches (but not bending). 相似文献
992.
993.
Xiao Liang Ting‐Ting Liu Zhi‐Ping Yan Yan Zhou Jian Su Xu‐Feng Luo Zheng‐Guang Wu Yi Wang You‐Xuan Zheng Jing‐Lin Zuo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(48):17380-17385
Pure organic materials with intrinsic room‐temperature phosphorescence typically rely on heavy atoms or heteroatoms. Two different strategies towards constructing organic room‐temperature phosphorescence (RTP) species based upon the through‐space charge transfer (TSCT) unit of [2.2]paracyclophane (PCP) were demonstrated. Materials with bromine atoms, PCP‐BrCz and PPCP‐BrCz, exhibit RTP lifetime of around 100 ms. Modulating the PCP core with non‐halogen‐containing electron‐withdrawing units, PCP‐TNTCz and PCP‐PyCNCz, successfully elongate the RTP lifetime to 313.59 and 528.00 ms, respectively, the afterglow of which is visible for several seconds under ambient conditions. The PCP‐TNTCz and PCP‐PyCNCz enantiomers display excellent circular polarized luminescence with dissymmetry factors as high as ?1.2×10?2 in toluene solutions, and decent RTP lifetime of around 300 ms for PCP‐TNTCz enantiomers in crystalline state. 相似文献
994.
Zhi‐Shuo Wang Mian Li Yun‐Lei Peng Zhenjie Zhang Wei Chen Xiao‐Chun Huang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(45):16217-16222
In the evolution of metal–organic frameworks (MOFs) for carbon capture, a lasting challenge is to strike a balance between high uptake capacity/selectivity and low energy cost for regeneration. Meanwhile, these man‐made materials have to survive from practical demands such as stability under harsh conditions and feasibility of scale‐up synthesis. Reported here is a new MOF, Zn(imPim) (aka. MAF‐stu‐1), with an imidazole derivative ligand, featuring binding pockets that can accommodate CO2 molecules in a fit‐like‐a‐glove manner. Such a high degree of shape complementarity allows direct observation of the loaded CO2 in the pockets, and warrants its optimal carbon capture performances exceeding the best‐performing MOFs nowadays. Coupled with the record thermal (up to 680 °C) and chemical stability, as well as rapid large‐scale production, both encoded in the material design, Zn(imPim) represents a most competitive candidate to tackle the immediate problems of carbon dioxide capture. 相似文献
995.
Yu Duan Zi‐You Yu Shao‐Jin Hu Xu‐Sheng Zheng Chu‐Tian Zhang Hong‐He Ding Bi‐Cheng Hu Qi‐Qi Fu Zhi‐Long Yu Xiao Zheng Jun‐Fa Zhu Min‐Rui Gao Shu‐Hong Yu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(44):15919-15924
The anode oxygen evolution reaction (OER) is known to largely limit the efficiency of electrolyzers owing to its sluggish kinetics. While crystalline metal oxides are promising as OER catalysts, their amorphous phases also show high activities. Efforts to produce amorphous metal oxides have progressed slowly, and how an amorphous structure benefits the catalytic performances remains elusive. Now the first scalable synthesis of amorphous NiFeMo oxide (up to 515 g in one batch) is presented with homogeneous elemental distribution via a facile supersaturated co‐precipitation method. In contrast to its crystalline counterpart, amorphous NiFeMo oxide undergoes a faster surface self‐reconstruction process during OER, forming a metal oxy(hydroxide) active layer with rich oxygen vacancies, leading to superior OER activity (280 mV overpotential at 10 mA cm?2 in 0.1 m KOH). This opens up the potential of fast, facile, and scale‐up production of amorphous metal oxides for high‐performance OER catalysts. 相似文献
996.
997.
Ming Ze Wu Zhi Long Ma Jian Yun Shi Xiu Juan Shi 《Journal of Coordination Chemistry》2019,72(22-24):3495-3501
AbstractSolvothermal reaction of a multidentate ligand (tetrakis[4-(1-triazolyl)phenyl]-methane (ttpm)), with Cd(NO3)2 afforded a cationic Cd(II) coordination polymer {[Cd(ttpm)·DMSO]·2NO3}n. Single-crystal X-ray diffraction analyses showed that ttpm belonged to the tetragonal space group I41/a, and 1 was a 2-D (4,4) network. 1-D channels along the c direction exist in the 3D stacking map to accommodate the charge-balancing NO3? anions. N2 adsorption/desorption experiments showed the framework had a BET surface area of 11.36?m2·g?1. Compared with luminescence of ttpm, 1 showed red-shifted luminescence spectra with higher intensity from the more rigid arrangement of the π systems. 相似文献
998.
Luqi Zhu Feifei Luo Zhi Li Ge Dai Pingang He Qingjiang Wang Qiming Chen 《Electrophoresis》2019,40(9):1331-1336
The release of cytochrome C (Cyt C) plays an important role in apoptosis. In this study, selective and sensitive detection of Cyt C based on an aptamer strategy coupled with MCE was developed. Following the binding of a specific aptamer to Cyt C, the aptamer exhibited an irregular state, reducing the binding affinity of a fluorescent probe, and thus preventing the aptamer‐Cyt C complexes from detection within the MCE. The height of the detection peak of the residual aptamer linearly decreased, and therefore, the difference in peak height of residual aptamer compared to that of the initial aptamer was used to quantify the captured protein concentration. Experimental conditions such as incubation time, pH, temperature, and ionic strength were optimized. A measurement of Cyt C concentration by MCE was achieved within 135 s, with a limit of detection as low as 0.4 nM. The proposed method has high selectivity and good stability for the detection of Cyt C. The experimental results demonstrate that this method is quick, consumes only a small quantity of sample, is highly selectivity and exhibits high sensitivity. 相似文献
999.
该文建立了婴幼儿配方乳粉中5种游离核苷酸的检测方法。婴幼儿配方乳粉经乙二胺四乙酸二钠和氯化钠溶液提取,强阴离子(SAX)固相萃取柱净化,通过反相Atlantis T3色谱柱分离,二极管阵列检测器检测,外标法定量。结果表明:方法抗干扰能力强、准确度高,尤其对羊奶粉净化效果好、分离度高。5种游离核苷酸在0.5~10 mg/L范围内线性关系良好(r≥0.999);添加水平在0.05~0.50 g/kg时,回收率为91.1%~112%,相对标准偏差为2.3%~4.7%;检出限为0.0010~0.0015 g/kg,定量限为0.0030~0.0045 g/kg。对乳粉质控样品进行检测,结果与中位值比较的偏差在10%以内。该方法可为监管部门提供技术支持,为乳品行业健康发展提供保障。 相似文献
1000.
通过浸渍法制备了一系列负载0.5%(重量百分比)Pd的氧化铈-氧化锆(NDK-84,由日本新日本电工株式会社提供)催化剂材料,并通过全面的表征手段,包括扫描电子显微镜(SEM)、透射电子显微镜(TEM)、高分辨透射电子显微镜(HR-TEM)、元素分布、X-射线衍射(XRD),氮气吸脱附测试与比表面积和孔径分布分析(BET)、X射线光电子能谱(XPS)等,研究了不同Pd前驱体和不同热老化处理条件、H2还原条件对Pd在铈锆固溶体上的分散、生长与烧结行为的影响,并评估了它们的三效催化活性.结果表明,热老化处理过程与还原过程显著影响了Pd在氧化物载体表面上的分散,因此导致不同的催化活性. 相似文献